November brings cooler temperatures

November was an exceptionally cool month in Denton, and relatively dry until the weekend before Thanksgiving. The promised “El Nino rains” haven’t materialized yet, but tropical storms from the Pacific had an unusually strong influence on our weather.

We started off cool with a high of only 60 degrees on November 1 and a near-freeze of 34 by the following morning. After warm-ups into the 70’s to near 80 for the next few days, a strong Arctic cold front blasted through North Texas on Veteran’s Day, November 11. Our first official killing freeze was reached the next morning with a low of 28, ending the growing season about a week earlier than usual.

The unusually strong and early cold front was the result of Super-Typhoon “Nuri.” Nuri never made landfall and that’s fortunate because peak wind gusts in the storm reached 185 mph. Nuri drifted north through the Pacific, where it was caught up in the Polar jet stream, producing a huge surface storm in the fishing grounds of the Bering Sea. It continued across Alaska into Canada, where it tapped into a pocket of frigid air in Yukon, pulling it down into the lower 48. Intense cold dropped south, affecting virtually every state from the Rockies eastward.

Subsequent cold fronts kept forcing cold air even deeper into Texas, resulting in a 17-degree low on the morning of November 18.

After a few warm days in the first half of the month, the successive cold-plunges dropped our average temperature for the month sharply below normal. As the month came to a close, our day-night average temperature was running about 49 degrees, nearly 8 degrees below normal for November.

Rainfall was sparse early in the month, with 1.43″ on November 4th and 5th. Another Pacific storm system, albeit warmer, was approaching North Texas with a potential for severe winds, hail and 1-2″ of rain on the weekend of November 22nd. Until that time, we had no severe storms, although south winds gusted to near 50 mph November 4th before our first cold front of the month.

At this time, the Climate Prediction Center is indicating cooler-than-normal temperatures and wetter-than-normal conditions in most of Texas during December, but there’s a catch.

The two previous forecasts were very similar, and based on El Nino continuing to strengthen in the Pacific. As it turned out, El Nino took a back-seat to tropical storm and typhoon activity in Asia. Shorter-range forecasts indicate a warm drying-trend for Texas during the first couple weeks of December.

With such uncertainty, it’s best to limit our forecast confidence to less than 10 days ahead.
Brad Barton is Chief Meteorologist of WBAP820/570KLIF/99.5 “The Wolf.”